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Your order will be upgraded from economy methods to ensure 1-3 business day delivery using UPS 3 day select and UPS ground regardless of weight or size. Place your order by 3:30 PM CST Monday through Friday and we'll ship it the same day. This offer is only available to the contiguous USA. Frozen foods and post office boxes do not qualify for upgraded shipping. See map below for transit times.*

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Osmolator Universal 3155 Auto Top Off - Tunze

Good, but you would expect more from a German made product. By Michaelon 12/2/2016

Michael would recommend this product to a friend

When I received the boxes at the door and opened them I was five stars for sure. As I was putting it together the hose for the Osmolator won't fit in the hole made in the Clear 5 Ga Trigger ATO container. OK, four stars (they should of coordinated thier product with some of the most popular ATO containers). I had to drill out, ouch, my laser cut hole with a drillbit stupid me, it chipped my brand-new ATO container. I should've just switched out the supplied hose with a standard sized one that I have, it must be because the German product is metric. Then pushing the hose into their own supply pump was really a pain. Once again the hose was too big or it's a very, very tight fit (please BRS, a warning on the fitment issue or a hose that will fit the hole and the pump would be nice). OK, three stars. Then in trying to mount the hose to the Ruby Trigger sump their own mounting bracket clip that they use is too small for the hose once again and the plastic screw in the hose holder is too big for the plastic clip. So outcomes the drill once more, luckily this time I didn't break anything. Should be down to two stars now but this is the best ATO on the market. OK, three stars. I hope I don't have any of the other problems in the other reviews that should be the most reliable and safety back up system there is. I've been running it for about an hour now.

Worked until it didn't workBy Timon 11/17/2016

Tim wouldn't recommend this product to a friend

Worked great for two weeks... now it is acting weird and not dispensing water. I have to manually unplug and plug it back it to get it to start working. It appears to be signalling the pump to start it every couple seconds. I can hear it inside my 5 gallon container. On then off constantly. Pump just kind of jerks on and off in water container.

could be better for the $$ we pay.By Devaon 11/2/2016

Deva wouldn't recommend this product to a friend

OK I got this ATO for my 90 reef. 1st think i noticed was the pump was crazy loud like the sound of airplane wings during landing. so I got a replacement for BRS same thing. tank is in my room and the pump wakes me up all the time.

next is that it its so sensitive ( a good thing) but it tunes on and off a few times a min. ( maybe that could be a fluctuation in my siphon but once again the load pump makes me cringe.

so all that i could live with barley . went on vacation and the power went out ( of course right things always happen when we are on vacation ) the power was off for a few hrs. once back on the ATO did not reset it self. so it failed got a txt from tank setter and had to have her pour water in sump my hand.

so all that said I would not recommend this ATO to many bugs for the price. going to order the micro smart ATO for my nano and see how that works.

I give it 2.5 stars...

Outstanding productBy Pedroon 9/29/2016

Pedro would recommend this product to a friend

It's been running for over 3 years flawlessly. Great features and very easy to install and use. Mostly set and forget. Don't forget to inspect and clean the little pump and sensors once a year... That is why Tunze name is huge.

one of the great products out there.By poetjimon 9/23/2016

poetjim would recommend this product to a friend

I have been using this auto fill for over a year and it has been great, i have found that the five gallon bucket that I keep under my 60 gal. max c tank has to be cleaned a couple of times a year and that:s it, i;m getting ready to get another one for my wife:s 25 gal.coral tank.

Other options less expensive and similar reliabillity.......By Jasonon 9/12/2016

Jason wouldn't recommend this product to a friend

I bought the Tunze Osmolator even though it was the most expensive ATO because I wanted to get the most reliable unit I could. Unfortunately over the last 4 months I've had continual problems with the unit. After the initial installation it would start and fill up to the optical sensor, but then a few minutes later kick back on and continue filling up to the back-up float switch. I run Kalkwasser in my ATO so that was pretty concerning.

After removing, cleaning and reinstalling the unit seemed to function ok for a couple weeks but not it kick's on the first time it's plugged in but stops after 15-20 seconds and never starts again. I've tried cleaning, repositioning the sensor etc. but no improvement.

Just buy the JBJ and keep the float switches clean on a regular basis.

Great idea just willl not function as promisedBy Joesreeftankon 9/4/2016

Joesreeftank wouldn't recommend this product to a friend

I have had this for about 18 months, I loved a raved about it at first, Problem I have had is the pump will stop shot. Tunze has sent me about 4 new pumps. They all do the same. pump will only run about 15 seconds. the controller says pump is on but its not on. I paid 200 for this system so I really wanted it to work, I am going to cut my losses now because as you all know this ATO is critical part of keeping my reef tank stable

Quit after less than 2 weeksBy BCon 7/8/2016

BC wouldn't recommend this product to a friend

After a loss of power,short term and yes it was on a surge power bar,Checked all aquarium,allOK.Wife comes in 1/2 hour latter says an alarm is buzzing.Checked it out sump high level ;luckily float stopped pump.So much for Tunze as Best ATO.

Easy top offBy Willon 6/20/2016

Will would recommend this product to a friend

I bought a 5 gallon tank next to my sump. Threw this in the tank with my RO/DI water and worked instantly. Very convenient, easy to use, accurate.

Awesome productBy Stevenon 6/13/2016

Steven would recommend this product to a friend

The Tunze Osmolator was a great purchase. I used to have to fill my sump manually every day. This allowed me to to focus more of my time on other areas of the system. I have it plugged into my Apex controller and programmed to shut of during feed mode to keep the alarm from going off. Also have the Apex to shut it down if the salinity in my take drops. Even without the Apex this would be a "must need" purchase.

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